Mr.Brown wants to make a rectangular pen for animals. He plans to use at least 120 feet of fencing,but no more than 200 feet. He wants the length of the pen to be three times the width and the width to be at least 30 feet. Use an inequality to show that Mr.Brown cannot do what he plans to do

Question

anonymous · Answer

$$w\geq 30$$
$$l = 3w$$
$$P=2l+2w=2\times 3w+2w=8w$$
$$P=8w\geq 8\times 30=240$$  but he wants 
$$P\leq 200$$ which is not possible since 
$$P\geq240$$